Multiple accessory operating mechanism



y 1945. v. J. PLOTKIN 7 2,403,102

MULTIPLE ACCESSORY OPERATING MECHANISM Filed Feb. 14, 1945 4 sheets-sheet 1 ATTORNEY July 2, 1946. v. J. PLOTKIN MULTIPLE ACCESSORY OPERATING MECHANISM 4 Sheets-Sh e et :5

Filed Feb. 14, 1945 r W i fl 0 J J g n dv w J 7 V F, m m

ATTORNEY y 1945- v. J. PLOTKIN 2,403,102

MULTIPLE ACCESSORY OPERATING MECHANISM Filed Feb. 14, 1945 4 Sheets-Sheet 4 I /IJ[ g 1/ I y .i w/ fi w w W M v f M, Z w .H nr 1 flrL, J 1 M .i| I: 3. M WA Z W W m M. E MLIM 5 W W M r7 /Z Z ATTORNEY w M J M T W m J w y M Wm M Eff 10 Z// N "I: l/0

BY v V Patented July 2, 1946 MULTIPLE ACCESSORY OPERATIN G MECHANISM Victor J. Plotkin, Los Angeles, Calif assignor, by

mesne assignments, to Lear,

Incorporated,

Grand Rapids, Mich., a. corporation oi Illinois Application February 14,.1945, Serial No. 577,901

20 Claims. 1

This invention relates to multiple accessory operatin mechanisms, and more particularly to mechanism for automatically opening and closing aircraft landing gear bay doors and lowering and raising landing gear in correct sequence.

In accordance with the present invention, a multiple accessory mechanism is provided comprising a driving. means connected to a planetary gearing including a driving element coupled to the driving means, a first driven element coupled to one accessory and a second driven element coupled to another accessory. The'arrangement is such that either one of the driven elements will be operated by the driving element depending upon which has the least torque resistance to operation. ing gear of aircraft, one of the planetary driven elements is connected through mechanicalactuators to operate the doors enclosing the landing gear bay or recess and the other driven element is connected through mechanical actuators to operate the landing gear. Under normal conditions, the mechanism is so designed that the initial torque resistance of the larding gear is greater than that of the doors. Ac .ordingly, when the As applied to the operation of landdriving means starts to op rate, there will be less torque resistance from t'. e actuators for the doors and the doors will be 0 med. At their limit of movement, the doors willoffer a greatly increased torque resistance and the mechanism will then operate to lower or raise the'landing gear. When this latter reaches its-limit of movement in either direction, the torque resistance developed thereby conditions the mechanism to raise the doors to their closed position.

It is among theobjects of this invention to proved a novel multiple accessory operating mechanism automatically operative to perform one or more operations in a predetermined sequence; to provide a multiple accessory operatto provide a simple, reliable, automatic actuator for raising and lowering aircraft landing gears and operating thecovers or doors for the landing gear bay or recess.

'Rhese and other objects, advantages and novel .features of the invention will be apparent from -l'-l of Fig. 2.

. 2 the following description drawings. In the drawings:

Fig. 1 is a diagrammatic perspective .view illustrating the invention as incorporated in an aircraft.

Fig. 2 is a side elevational lview of a multiple accessory operating mechanism.

Fig. 3 is a longitudinal sectional view, on the line 3--3 of Fig. 2 through a portion of the mechanism shown in Fig. 2.

'4 isa transverse sectional view on the line Fig. 5 is a sectional view, looking in the direction of the arrows, on the line 5 5 of Fig. 4.:

Fig. 6 is a bottom plan view, with the cover removed, on the line 6-6 of Fig. 2.

Fig. 7 is a reduced cross-sectional view, looking in the direction of the arrows, on the line 'l-'l of Fig. 3.

Fig. 8. is a transverse cross-sectional view on the line 8-8 of Fig. 3, looking in the direction of the arrows.

Fig. 9 is a schematic exploded view of the mechanism shown'in Fig. 2. I 1

Fig. 10 is a schematic wiring diagram illustratin a. control circuit of the invention.

Referring to the drawings, the multiple accessory operating mechanism I0 of the invention is illustrated as arranged to operate the landing gear and landing gear bay doors of an aircraft I5, the forward portion of which is illus-trated in dotted outline. For this purpose, operating elements of mechanism III are connected by flexible shaftings II, II to actuators 20, 20' coupled to operate doors 25, 25' for the landing gear bay of aircraft I 5. Other operating elements of mechanism I0 are connected by flexible shaftings I2, I2 to actuators 3.0. 30' which are coupled through linkage, indicated generally at I3, I3, to struts I4, I4 of landing gear 35, 35'. 1

Suitable electric control circuits are connected to control an electric motor forming part of mechanism III. As will be described,-when the control circuit is conditioned to effect lowering of the landing gear, mechanism ID will first operate to lowerdoors 25, 25' through actuators 20, 20' and, when the doors have reached the limit of their opening movement, will lower landing gear 35, 35'

- through actuators 30, 30'. When the landing gear has reached its lower limit of movement, mechanism ID will automatically be conditioned to close doors 25, 25' through operation of actuators 20, .20. Similarly, when it is desired to raise the landing gear, mechanism ID will first open doorsv 25, 25" and then raise landing gear 35, 35' to its and I accompanyin v gearing units.

,as may also be linkages l3, I3. arrangements for operating the landing gear and upper position, wherein' it is latched by suitable means well known to those skilled in the art,-

and mechanism ill will then close doors 25, 25'. Each of suchsequences of operation takes place automatically upon the closingof a suitable switch motor for mechanism I is automatically deener g-ized, through opening of its energizing circuit.

More specifically, driving elements, of mechanism H! are connected through cables ,1 I, to gear boxes l6, I6 which may be hingedly c'on- K operates landing gear 35, 35' to either the exnected to a suitable fixed portion of aircraft l5.

Actuators 23, 26' either may be jack screws of the type described and claimed. in -Wi1liam P.

Lears Patent No. 2,319,463 issued May 18, 1943,

for Mechanical actuator systems, or may be suitable reductiongearing units operable by the gearing in gear housings l6, l6. Similarly, flexible cables l2, l2 connect other driving elements of mechanism in to gear housings I1, |1' connected to actuators 30, Actuators 30, 30' inay likewise be of the type described and claimed in said Lear patent,-or may be suitable reduction Gear housings I1, I I may be pivotally connected to a fixed portion of aircraft l5, The illustrated I scribed more fully hereinafter, includes a driving member coupled, through torque responsive de-- vice 50, to motor 40. It also includes a first driven element coupled to flexible shaftings II, II through coupling elements secured to threaded Asecond driven element of the planetary gearing ls coupled to flexible shaftings I2 01' |2-' through coupling elements secured to threaded bosses 22, 22'.

Torque responsive device 50 is adapted to operate switch means contained in a control box 55.

As will be explained, torque responsive device 50 1 may be manually operated to operatively un-- couple motor from planetary gearing through the medium of a cable connected to a bar 23 slidablymounted in control box 55. Bar

23 is provided with a depending flange or ear 24 slidably engaging a rod 26 coupled to a brake release mechanism 60. Rod 26 is provided with a collar 21 whereby, when bar 23 ,is pulled to the left, as shown in Fig. 2, flanges 24 will engage 4 collar 21 and move rod 26 to the left.

Brake means 60 normally locks the aforementioned second driven element of planetary gearing 45 against rotation. Rod 26 is connected to doors 25, 25' and when these doors reach their fully open position, rod 26 is moved to the left,

tended or retracted position through the second driven element of planetary gearing 45. When the landing gear has reachedits extent of movement in either direction, torque responsive device 50 operates the switch means in control box 55 to effect circuit connections for motor 40 in a direction to close doors 25'. When doors 25 reach the closed position, torque responsive device 53 operates switch means in control box 55 to deenergize the motor.

Referring more particularly to Figs. -3 through 6, motor 40 is provided with a drive pinion 3| engaging a plurality .of pinions 32 each rotatably mounted through bearings 33 on shafts 34 mounted in disks 36 and 31'. Disks36 and 31 are interconnected by studs 36 provided'with extensions 4| slidably supporting a braking disk 42 for axial movement with respect to disk 31. The purpose of this arrangement will be describedhereinafter, Pinions 32 mesh with a ring gear 43 rotatably mounted on bearings 44in housing 46 of torque,

responsive device 50. The outer periphery of ring gear 43 is provided with circumferentially spaced notches 41.

Control box 55 is secured to a boss 5| on housing 46. A sleeve member 52 is pivotally mounted on pins 53, 53 disposed inboss 5| and a plunger 54 is slidably mounted in sleeve member 52. The upper end of plunger 54 normally is urged into engagement with one of the notches 41 by a spring 56 surrounding a, reduced portion of the plunger and engaged between a shoulder in sleeve member 52 and a shoulder of plunger 54. The

lower end 51 of plunger 54 extends outwardly through sleeve member 52 and acts as a pivotal support for a cam 53. cam 58 is provided with a triangular shoulder 6| normally engaging a triangular notch 62 in the lower end of sleeve member 52. A pin 63 extends through the lower end of portion 51 of plunger 54.

to the left as viewed in Fig. 2, cam 58 is rotated I so that its shoulder 6| is moved out of notch 62. The cam is thereby moved downwardly and through engagement with pin 63 moves plunger 54 downwardly against the force of spring 56. This releases the upper end of the plunger from engagement with ring gear '43, permitting this ring gear .to rotate. The purpose of this arrangement .will be described hereinafter.

A pair of snap action control switches 15 and,

80 are mounted in control box 55. The plungers 16 and 11 of these switches are engaged by sleeve member 52. Sleeve member 52 is normally biased to a vertical position by adjustable means secured to control box 55, This means comprises apair of plungers '13, 18 mounted in tubular housings 19 secured to the control box. Plungers 18 are normally urged outwardly by springs 3| engaging the inner ends of the plunger and adjustable member 82 threadedly engaged in a nipple-83 threadedinto housing 13. Adjustable rods-32 are providedwith a head for engagement with a screw driver or other means to adjust the pressure of springs 8| against plungers", and the,

adjustment may be fixed by lock'nut 8 5 engaging members 82. By suitable. adjustment of members 82, the pressure of plungers 18 biasing sleeve member 52 to the vertical position may be preset at any desired value.

The arrangement thus far described operates as follows. When motor 40 is energized, its pinion 3| rotates pinions 32 which roll around the inthe energization of motor 40 to accomplish automatic sequential operation mechanism I0.

Disks 31 and 42 form part of a centrifugal governor for limiting the rate of operation of the landing gears and doors. For this purpose, disk '31 is provided with radially outwardly tapered surface slots 86 in which are mounted centrifugal means such as balls 81. When the speed of rotation of disks 31 and 42 exceeds a preselected value,

balls 81 move radially outwardly in slots 86 to.

mechanically bias disk 42 against a braking surface 88 secured to a wall of housing 46. This effects a braking action on torque device 50 and consequently upon the elements of mechanism I0 connected thereto.

Disk 31 is formed integrally with a shaft 9I mounted in a bearing 92 in the housing of planetary gearing 45. Driving pinion 95 of planetary gearing 45 is mounted on the outer end of shaft 9I, which has a reduced portion 96. A bearing 91 on reduced portion 96 rotatably supports a shaft drives gear I20 through key I 2I (in the event brake 60 is disengaged). As gear I20 rotates, pin I tends to ride out of depression I23 and in so doing engages one of the ends of split sleeve I24 urging the sleeve to expand'against bevel gear I26 and drive the same. However. as there is no positive driving-connection between shaft I08 and bevel gear I26, these elements may slip with respect to each other in the event of excessive torque onybevel gear I26. The outer reduced end I21 of shaft I08 is mountedin a bearing I28 in an end wall I80 of housing Il'l.

Bevel gear I 26 meshes with a pair of bevel gears I3I. I3I each secured to a shaft I32 having a splined outer end I33 disposed in threaded nipples 22, 22'. Shafts I32 are rotatabl mounted in bearings I34 inextensions l35 of housing 1..

Nipples 22, 22' are secured to extensions I85 through the medium of studs I36. Splined portions I33 are connected to shaftings I2, I2

, through the medium of coupling members secured ports a plurality of planetary pinions I00 rotatably mounted, through bearings IN ,on shafts I02 supported in the spider, Pinions IOI engage an internal ring gear I03 forming the above mentioned first driven element of the planetary gearing. Ring gear I03 includes a disk I04 rotatably supported through a bearing I05 on shaft 9i. It also includes a generally channel shaped member I06 rotatably supported through a bearing I01 on a shaft I08 formed integral with spider 98.

The external periphery of ring gear I03 is formed with gear teeth meshing with a pair of pinions IIO each secured to a shaft III rotatably supported in bearings I I2 in extensions I I3 of the housing of planetary gearing 45. Shafts I II are provided with splined ends II 4 disposed in threaded nipples 2|, 2|. Splined portions I I4 are adapted to be secured to flexible shaftings I2, I2 through coupling members secured to threaded nipples 2 I, '2I, v

' The intermediate portion of shaft I08 is mounted in a bearing 'I I5 supported in a partition II-6 securedto the housing II1 of planetary gearing unit 45 through the medium of studs II8. .Adjacent bearing 5,. a gear I20 is secured to shaft I08 through the medium of a key I2I. Gear I20 is operatively associated with brake mechanism 60 in a manner to be described hereinafter, and is formed with a hub portion I22 provided with a depression I23 as shown in Fig. 8. A split sleeve I24 surrounds hub portion I 22 and a pin I25 vis disposed in depression I 23 between the ends'of sleeve I24. A bevel gear I26 is mounted on sleeve The described arrangement acts as a slipping clutch. When torque is applied to shaft I 2|, this to nipples 22, 22'.

Brake device 60 is more clearly illustrated in Fig. 8. As shown, a housing I40 is secured to housing II1 by studs I4I. Housing I40 has therein a bearing I42 engaginga rod I43 having a forked lower end I44. A gear segment I45 is secured to the upper end of rod I43 and is urged into engagement with gear I20 by a spring I46 engaging gear segment I45 and bearing I42.

Referringto Fig. 2, a crank I41 is pivotally mounted in a pair of ears I48 on the lower .end' of housing I40 and has one arm pivotally connected to the forked end I44 of rod I43 by a pin I50, and the other arm pivotally connected to a. fork I5I by pin I52. Fork I5I is adjustably secured to the right hand end of rod 26.

The mechanical operation of mechanism I0 will be apparent'by reference t the schematic Therefore ring gear I03 of planetary gearing 45 is rotated clockwise through the medium of plan etary pinions I00, driving pinions H0, H0 to rotate flexible shafting'II, II. This lowers doors 25, 25'.

When the doors are fully opened, they move rod 26 to the left, as viewed in Figs. 2 and 9.

Through the medium of crank I41, this moves plunger I43 downwardly disengaging gear segment I45 from gear I20. As the doors are in landing gear 35, 35'.

the fully opened position, gear I03 is prevented from turnin further due to the braking effect I of pinions IIO. ,Accordingly, spider 98 turns counter clockwise rotating gear I 20 and bevel gear I26. This, in turn, rotates bevel gears I3I,- which, through the medium of flexible shafting I2, I2, operates actuators 30, 30 to retract the When the landing gear is in a counter clockwise direction.

I deenergize motor 00.

f v n, 'n', actuators a, 20' are operated to move the doors toward a closed position. Immediatelyv after the doors start to move toward a closed position, rod 20 is released and spring I of brake unit 00 thereupon urges gear segment I00 into locking engagement with gear I20. When exerted on ring gear 00 tends to rotate this gear This swings sleeve member 02 in a direction to release plunger 11 and depress plunger of switch 10. Thi opcrates switch 15, ina manner to be described, to

is' again rotated counter clockwise rotating gear I00 clockwise and pinion I I0 counter clockwise to open the doors in the manner previously described. when the doors are fully opened, gear segment I00 is released from gear I20 as previously described. Rotation of motor 0II tends to rotate gear I20 counter clockwise, but this is prevented as the landing gear is in the retracted position. Accordingly, a counter torque is developed in ring gear 00 which oscillates clockwise to operate switch 00 reversing the direction of rotating of motor 00. The motor then rotates in a direction to drive gear I20 clockwise and lower the landing gear 05, 05 through flexible shafting i2, I2. The lowering operation, due to the effect of gravity on the landing gear, takes place with an aiding torque.

When the landing gear has reached the" limit of its-lower position, spider 00 can move 'no further. Shaft 0| through pinion 00 thus will rotate gear I00 in a counterclockwise direction and pinions H0 in a clockwise direction to raise doors 25, 25' through flexible shafting II, II'. When the doors are fully closed, a counter torque is developed in ring gear 03, which oscillates in a counter clockwise direction to operate switch 15. In a manner to be described, switch 15 breaks the energizing circuit for motor 00 and mechanism I0 comes to a stop. v

The gear may also be lowered by gravity. For this purpose, a suitable operating cable is attached to bar 20. When this bar is pulled to t the left as viewed in Figs. 2 and 9, plunger 50 is withdrawn into sleeve member 52 against the force of spring 50. It thus disengages ring gear 00. At the same time, flange secured to arm 23 engages collar 21 on rod 20. Rod 20 is thus likewise pulled to the left and through crank 01 releases gear segment I05 from'gear I20. Thus,

the doors are free to open and the landing gear is free to move to the extended position under the influence of gravity. I A typical electrical circuit for eifecting automatic operation of mechanism I0 is illustrated in Fig. 10. Motor 00 is illustrated as a compound motor having an armature winding I00, a shunt The arm is interconnected with" switch blades the'doors 'are fully closed; the counter torque I00 and I01 are engaged respectively with contacts I02 and I00. Switch blades I00, I01 are commonly connected to thepositlve terminal of a suitable source of current I01 through the medium of "up limit switch I00. Switch blades I00, I00 are connected to source I01 through down" limit switch I00. Source I01 may be the usual 28 volt battery or generator carried aboard the aircraft.

As the landing gear is down, limit switch I00 will be open. Engagement of switch I00 with contact I02 connects one terminal of a relay Hi to the positive side of source I" through "up" limit switch I00 and-conductor I10. The other terminal of relay "I is connected by a conductor I12 to ground I10, which latteris electrically identical with the ground I10 connection to the negative terminal of source I01. Relay I1I engages its armature I10 with its front contact I10. Contact I10 is connected to conductor I10 which is connected to the positive terminal or source I01. Armature I10 is connected to one terminal of shunt-field winding I00, the other terminal of which is connected to ground at I11. Accordingly, energization of relay I1I eflects energization of shunt field winding I00. Armature I10 also closes a holding circuit for relay "I through I armature I00 and series field I10 as follows.

front contact 2I0 and blade 2I0 of snap switch 15, so that relay I1I remains energized after limit switch I00 opens when the landing gear is fully retracted.

Engagement of switch I01 with contact I00 connects the positive side of source I01 to switch 00. This switch is illustrated as comprising a three pole, double throw reversing switch including three blades I10, I00, I. Normally, blade I10 is disengaged from contact I02 and blades I00 and IOI are engaged with contacts I00 and I00 respectively. Blades I00 and IOI are connected to contacts I00 and 22I of switch I10. A conductor I05 connects contact I00 to one terminal of "up relay I00. The opposite terminal of relay I00 is connected to ground through conductor I12. Energization of relay I00 engages its armatures I01 and I00 with front contacts I00 and IOI, respectively. A holding circuit for relay I00 is completed through switches I00 and Ill. front contact I00, relay armature I01, conductor I00 and junction point I02. Therefore, relay I00 will remain energized even though up' limit switch I00 opens when the landing gear has been fully retracted.

Relay I00 controls the energization of motor One terminal of field I10 is connected through conductor I10 to the positive terminal of source I01. connected to junction point I02. Conductor I00 connects junction point I02 to armature I01 of relay I00. A conductor I00 connects junction point I02 to one terminal of a relay I00. Accordingly, motor armature I00 and series field winding I10 are energized over the following circuit: positive terminal of source I01, field I10, junction point I02, conductor I00, relay armature I01, front contact I00, conductor I00, motor armature I00, conductor I01, back contact I00 of relay 200, relay armature 20I, conductor 202 .startingresistance 200 and ground I10. A parallel circuit is also closed through relay I05, which engages its armature 200 with front contact 200 to shunt starting resistance 200.

The doors then open in the manner previously described. When fully open, the doors release gear segment from gear I20, so that con- The other terminal of the field winding is tinued operation of motor 40 in the same direction will retract the landing gear in the manner set. forth above. When the landing gear is 80. This engages switch blade I18 with contact I82 and disengages switch blades I80, I8I' from contacts I83, I84, respectively. The holding circuit for relay I86 is broken, and its armature I88 engages back contact 206. At the same time, an energizing circuit for relay 200 is completed through engagement of switch I18 with contact I82. However, relay 200 is a delayed pick-up relay.so that its armature 20I remains in engagement with its back ,contact I 88 for a short interval. A dynamic braking circuit for motor 40 is thus completed through conductor I96, relay contact 206, relay armatures I88 and 2!, relay contact I98 and conductor I91. As shunt field winding I65 remains energized, motor armature I60 is quickly brought to a stop.

The energizing circuit for relay I95 is likewise broken by disengagement of relay armature I88 from front contact I9I. However, after a predetermined interval, relay 200 engages its armatures 20I and 208 with contacts 2I0 and 2I I, respectively. This completes an energizing circuit for motor armature I60 and series field winding I10 for rotation of the motor in the opposite direction. This circuit, as far as conductor I93, is as previously described; From conductor I93, the circuit includes relay armature 208, front contact 2| I, conductor I91, motor armature I60, conductor I96, contact 206, relay armature I88, conductor 202, starting resistance 203 and ground I13. A holding circuit for relay 200 is completed through switch. blade 2I5 of. switch 15, conductor I91, relay contact 2| I, relay armature 208, and conductor I93 to junction point I92. Relay 200 thus remains energized when switch is restored to the position shown in the drawings. Relay I95 is again energized through having its one terminal connected to ground at contact 2I0, and closes its armature 204 to shunt resistance 203. -,Motor 40 then operates in a direction to close doors 25, 25, as previously described.

When the doors reach their closed position, counter torque is again .developed in ring gear 43, which swings sleeve member 52 in a direction to disengage plunger 11 and depress plunger 16 of switch 15. This disengages switch blades 2I5 and. 2I6 from contacts 2" and 2I8 breaking the holding circuit for relay HI and relay 200. However, relay I1 I remains energized through engagement of switch blade. I56 with contact I65 as switch I15 is still in the up position. Relay 200 disengages its armatures.20l and 208 from.

the circuit for shunt field windings I65 through .lower doors 35, 35.

10 back contact 22.2 and "down limit switch I66. Switch blade I is connected to the positive terminal of source I61 through switch blade I58,

contact HI and down limit switch I66 which is also as previously described. 'Relay 200 is energized as previously described to effect operation of motor 40 in the opposite direction. The landing geartherefore is lowered with an aiding torque. When the landing gear has been fully lowered, spider 98 is locked against movement and continued rotation of motor 40 will raise the doors to their upper position. When the doors are fully closed, the counter torque developed in I gear 43 operates the switch 15 to break the energizing circuits for motor 40 as previously described, and bring the mechanism to a stop.

It will be noted that switches 15 and 80 also limit the maximum torque of mechanism I 0. Any excessive load on the gear drive and the ring gear 43, will tend to rotate ring gear 43 in one direction or the other thus operating one or the other of switches 15 or 80 to either stop motor 40 or reverse the direction of rotation thereof until such time as the torque has dropped below such overload value The described invention comprises a compact unit which is operable to effect the operation of two accessories depending upon which accessory requires the leasttorque to operate the same at any given time. It is particularly adaptable for operating the landing gear and landing gear bay doors of an aircraft. The operation is entirely automatic once the mechanism is conditioned for operation of the landing gear in a particular direction. The torque responsive device 50 also provides overload protection for this system, eliminating the necessity for slippin clutches, extra fuses, or other additional elements.

While a specific embodiment of the invention has beenshown and described in detail to illustrate the application of the principles thereof, it will beunderstood that the invention may be otherwise embodied without departing from such principles.

What is claimed is:

v 1'. A multiple accessory operating mechanism comprising, in combination, a power drive means; planetary gearing including a driving element coupled to said power drive means, a first driven element coupled to a first accessory and a second driven element coupled to a second accessory; brake means normally locking said second driven element against movement whereby, when said power drive means is energized, said driving element, through said first driven element, will operate such first accessory from a first limiting position to a second limiting position; and means operable by such first accessory, when it attains its second limiting position, to release said brake means from said second-driven element, whereby said driving element, through said second driven element, will operate such second accessory from This first breaks the circuit a first limiting position to a second limiting position. 7

2. A multiple accessory operating mechanism comprising, in combination, a power drive means! jplanetary gearing including a, driving element coupled to said power drive means, a first driven element coupled to a first accessory and a second driven element coupled to a second accessory;

brake means normally locking said second driven element against movement whereby, when said power drive means is energized, said driving element, through said first driven element, will operate such first accessory from a first limitin position to a second limiting position; means. operable by such first accessory, when it attains its second limiting position, to release said brake means from said second driven element, whereby said driving element, through said second driven element, will operate such second accessory from a first limiting. position to a second limiting posi-. tion and a torque responsive device coupled between said power drive means andsaid planetary gearing and operable, when such second accessory attains its second limiting position, to energize said power drive means in the reverse direction whereby said driving element, through said first driven element, will operate such first accessory from its second limiting position to its first limit- :ing position.

3. A multiple accessory operating mechanism comprising, in combination, a power drive means gplanetary gearing including a. driving element coupled to said power drive means, afirst driven element coupled to a first accessory and a second driven element coupled to a second accessory;

brake means normally locking said second driven element against movement, whereby, when said power drive-means is energized,said driving element, through said first driven element, will opsaid driving element, through said second driven element, will operate such second accessory from }a first limiting position to a second limiting position; and a torque responsive device coupled between said power drive means and said planetary gearing and operable, when such second accessory attains its second limiting position, to energize said power drive means in the reverse direction whereby said driving element, throughsaid first driven element, will operate such first accessory from its second limiting position to itsfirst limiting position; said device being operative, when such first accessory attains its first limiting position, to deenergize said power drive means.

4. A multiple accessory operating mechanism comprising, in combination, a. power drive means;

planetary gearing including a driving element coupled to said power drive means, a first driven element coupled to a first accessory and a second driven element coupled to a second'accessory;

brake means normally locking said second driven element against movement whereby, when said I power drive means is energized, said driving element, through said first driven element, will operate such first accessory from a first limiting position to a second limiting position; means operable by such first accessory, when it attains j its second limiting position, to release said brake means from said second driven element, whereby said driving element, through said second driven element, will operate such second accessory from 75 comprising, in combination, a reversible electric a first limiting position toa second limiting posi- 7 tion; and manually operable means operatively associated with said gearing and effective, when operated, to uncouple said power drive means from said planetary gearing and to release said brake means to provide for movement of such accessories under the influence of gravity.

5. A multiple accessory operating mechanism comprising, in combination, a power .drive means; planetary gearing including a driving element coupled to said power drive means, a first driven element. coupled to a first accessory and a second 7 drlven element coupled to a second accessory;

tion; and a speed governor effective to limit th rate of operation of such accessories.

6. A multiple accessory operating mechanism comprising, in combination, an electric motor; planetary gearing including a driving element coupled to said electric motor, a first driven element coupled to a first accessory and a second driven element coupled to a second accessory;

brake means normally locking said second driven element against movement whereby when said electric motor is energized, said driving element, through said first driven element, will operate such first accessory from a first limiting position to a second limiting position; and means operable by such first accessory, when it attains its second limiting position, to release said brake means from said second driven element, whereby said driving element, through said second driven element, will operate such second accessory from a first limiting position to a second Iimiting position.

7. A multiple accessory operating mechanism comprising, in combination, a reversible electric motor; planetary gearing including a driving eletween said electric motor and said planetary gearment coupled to said electric motor, a first driven element coupled to a first accessory and a second driven element coupled to a second accessory;

brake means normally locking said second driven such first accessory, when it attains its second limiting position, to release said brake means from said second driven element, whereby saidv drivingelement, through said second driven element, will operate such second accessory from' a first limiting position to a second limiting position; and a'torque responsive device coupled being and operable; when such second accessory attains its second limiting position, to energize said its second limiting position to its first limiting p sition.

8. A multiple accessory operating mechanism second limiting position, to release said brake means from said second driven element, whereby said driving element, through said second driven element, will operate such second accessory from a first limiting position to a second limitingposition; and a torque responsive device coupled between said electric motor and said planetary gearing and operable, when such second accessory attains its second limiting position, to energize said electric motor in the reverse direction whereby said driving element,

through said first driven element, will operate such first accessory from its second limiting position to its first limiting position; said device being operative, when such first accessory attains its first limiting position, to deenergize said electric motor.

9. A multiple accessory operating mechanism comprising, in combination, an electric motor;

planetary gearing including a driving element coupled to said electric motor, a first driven element coupled to a first accessory and a second driven elementcoupled to'a second accessory: brake means normally locking said second driven element against movement whereby when said electric motor is energized, said driving element, through said first driven element, will operate such first accessory from a first limiting position to a second limiting position; means operable by such first accessory, when it attains its second limiting position, to release said brake means from said second driven element, whereby said drivin element, through said second driven element, will operate such second accessory from a first limiting position to a second limiting position; and manually operable means operatively associated with said gearing and effective, when operated, to uncouple said motor from said planetary gearing and to release said brake mean to provide for movement of such accessories under the influence of gravity.

10. A multiple accessory operating mechanism comprising, in combination, an electric motor; planetary gearing including a driving element coupled to said electric motor, a first driven element coupled to a first accessory and a second driven element coupled to a second accessory; brake means normally locking said second driven element against movement whereby when said electric motor'is energized, said driving element,

" pivotally mounted retractable element normally through said first driven element, will operate such first accessory from a first limiting position to a second limiting position; means operable by such first accessory, when it attains its second limiting position, to release said brake means from said second driven element, whereby said driving element, through said second driven element, will operate such second accessory from a firstlimiting position to.a second limiting position; and a speed governor efie'ctive to limit the rate of operation of such accessories.

11. A multiple accessory operating mechanism comprising, in combination, an electric motor;

' ernor effective to limit the rate planetary gearing including a driving element coupled to said electric motor, a first driven element coupled to a first accessory and a second driven element coupled to a second accessory;

. brake means normally locking said second driven limiting position, to release said brake means from said second driven element, whereby said driving element, through said second driven element, will operate such second accessory from a first limiting position to a second limiting position; manually operable means operatively a's-- sociated with said gearing and effective, when operated, to uncouple said motor from said planetary gearing and to release said brake means to provide for movement of such accessories under the influence of gravity; and a speed govof operation of such accessories. i

comprising, in combination, an electric motor; reduction gearing, including a normally stationary movable member, coupled to said motor; a

engaged with said movable member; switch means operable by said retractable element to control the energization of said motor; adjustable means restraining movement of said retractable element and said movable member; planetary gearing including a driving. element coupled to said reduction gearing, a first driven element coupled to a first accessory and a second driven element coupled to a second accessory; brake means normally lockin said second driven element against movement whereby when said electric motor is energized, said driving ele ment, through said first driven element, will op erate such first accessory .from a first limiting position to a second limiting position; and means operable by such first accessory, when it attains its second limiting position, to release said brake said driving element, through said first driven I element, will operate such first accessory from its second limiting position to' its first limiting position.

13. A multiple accessory operating mechanism comprising, in combination, an electric motor;

reduction gearing, including a normally station ary movable member, coupled to said motor; a pivotally mounted retractable element normally engaged with said movable 'member; switch means operable by said retractable element to control the energization of said motor; adjustable means retraining movement of said retractable'element and said movable member; planetary gearing including a driving element coupled to said reduction gearing, a first driven element coupled to a first'accessory and a second driven element coupled to asecond accessory; brake means normally locking said second driven 12. A multiple accessory operating mechanism,

element against movement whereby when said electric motor is energized, said driving element,

-through said first driven element, will operate such first accessory from a first limiting position to a second limitingposition; means operable by such first accessory, when it attains its .second limitingposition, to release said "brake means from said second driven element, whereby said driving element, through said, second driven element, will operate such second accessory from a first limiting position to a second limiting position; said movable member, when such second accessory] attains its second limiting position, moving in response to the counter torque thereupon to swing said retractable element to selec-' tively operate said switch means to energize said electric motor in the reverse direction whereby said driving element, through said first driven element, will operate such first accessory from its second limiting position to its first limiting position; and said movable member, when such first accessory attains its first limiting position, moving in response to the counter torque thereupon to swing said retractable element to selectively operate said switch means to deenergize said motor. i

14. A multiple accessory operating mechanism comprising, in combination, an electric motor; reduction gearing, including a normally stationary movable member, coupled'to said motor; a

pivotally mounted retractable element normally engaged with said movable member; switch means operable by said retractable element to control the energization of said motor; adjustable means retraining movement of said retractable element and said movable member; planetary gearing including a driving element coupled to said reduction gearing, a first driven elementcoupled to afirst accessory and a second driven element coupled to a second accessory; brake means normally locking said second driven element against movement whereby when said electric motor is energized, said driving element,

16 comprising, in combination, an electric motor; reduction gearing, including a normally stationary movable member, coupled to said motor; a pivotally mounted retractable element normally engaged with said movable member; switch means operable by said retractable element to control the energization of said motor; adjustable means I retraining movement of said retractable element and said movable member; planetary gearing including adriving element coupled to said reduction gearing, a first driven element coupled to a first accessory and a second driven element coupled to a second accessory; brake means normally locking said second driven element against movement whereby when said electric motor is energized, said driving element, through said first driven element, will operate such first accessory from a first limiting position to a second limiting position; brake releasemeans operable by such first accessory, when it attains its second limiting position, to release said brake means from said second driven element, whereby said driving ele- I ment, through said second driven element, will operate suchsecond accessory from a first limiting position to a second limiting position; said movable member, when such second accessory attains its second limiting position, moving in response to the counter torque thereupon to swing said retractable element to selectively operate said switch means to energize said electric motor in the reverse direction whereby said driving element, through said first driven element, will operate such first accessory from its second limiting position to its first limiting position; said movable member, when such first accessory attains its 'first'limiting position, moving in response to the counter torque thereupon to swing said retractable element to selectively operate said switch through said first driven element, will operate such first accessory-froma first limiting position to a second limiting position; brake release means operable by such first accessory, when it attains its second limiting position, to release said brake means from said second driven element, whereby said driving element, through said second driven element, will operate such second accessory from a first limiting position .to a second limiting position; said movable member, when such second accessory attains its second limiting position,

- moving in response to the counter torque thereupon to swing said retractable element to selectively operate said switch means to energize said electric motor in the reverse direction whereby said driving element, through said first driven element, will. operate such first accessory from its second limiting position to'its first limiting position; said movable member, when such first accessory attains its first limiting position, movving in response to the counter torque thereupon r to swing said retractable element to selectively operate said switch means to deenergize said motor; and manual means coupled to said retractable element and to said brake release means and effective, when operated, to withdraw said retractable element from engagement with said movable member and to release said brake to opermeans to deenergize said motor; a centrifugal governor coupled between said reduction gearing and said planetary gearing and effective to limit the rate of operation of such accessories; and manual means coupled to said retractable element and to said brake release means and effective, when operated,to withdraw said retractable element from engagement with said movable member and to release said brake to operatively uncouple said motor from said planetary gearing to provide formovement of such accessorie under the influence of gravity.

16. An aircraft landing gear and landing gear bay door operating mechanism comprising, in combination, an electric motor; first actuator means operable to move the doors between open atively uncouple said'motor from said planetary gearing to provide for movement of such accessories under the influence of gravity. 15. A multiple accessory operating mechanism and closed positions; second actuator means operable to move the landing gear between extended .means when the doors are fully open whereby said driving element, through said second driven element, will operate said second actuator means to retract said landing gear.

1'7. An aircraft landing gear and landing gear,

bay door operating mechanism comprising, in combination, an electric motor; first actuator means operable to move the doors between open to retract said landing gear; a torque responsive a predetermined value, to deenergize or reverse said first driven element, will operate said first 17 v .and closed positions; second actuator-means operable to move the landing gear between ex-. tended and retracted positions; planetary gearing including a driving element coupled to said motor, a first driven element coupled to said first actua tor means and a second driven element coupled, to said second actuator means; brake means normally locking said second driven element against movement whereby when said motor is energized, said driving element, through said first driven element, will operate said first actuator means to open such doors; release means coupling said brake means to the doors to release said brake means whenthe doors are fully open whereby said driving element, through said second driven u element, will operate said second actuator means device coupled between said motor and said driven element; and switch means selectively operable by said device, when the torque thereon exceeds 20 the direction of, rotation of said motor; said torque responsive device, when such landing gear is fully retracted, operating said switchmeans to reverse said motor whereby said driving element, through said first driven element, will operate said first actuator means to close, such doors; said device, when the doors are fully closed, operating said switch means to deenergize said motor; said torque responsive device, when said motor is energized with the landing gear in the retracted positionand the doors have fully opened, operating said switch means to reverse the direction of rotation of said motor'whereby said driving element, through said second driven element, will operate said second actuator means to extend the landing gear and said device, when the landing gear is fully extended, operating said switch means to again reverse the direction of rotation of said motor whereby said planetary 40 gearing will operate said first actuator means-to close said doors; said device, when the doors are again fully closed, operating said switch means to deenergize said motor.

18. An aircraft landing gear and landing gear bay door operating mechanism comprising, in combination, an electric motor; first actuator means operable to move the, doors between open and closed positions; second actuator means op erable to move the landing gear between extended and retracted positions; planetary gearing including a driving element coupled to said motor, a first driven element coupled to said first actuator means and a second driven element coupled to said second actuator means; brake means normally locking said second driven element against movement ,v whereby when said motor is energized, said driving element, through actuator means to open such doors; release means coupling said brake means to the doors to release said brake-means when the doors are fully open whereby said driving element,through said second driven element, will operate said second actuator means to retract said landing gear; a torque responsive device coupled between said motor and said driven element; switch means iii) ' selectively operable by said device, when the doors under the influence of gravity;

means to'close such doors; said device, when theagain reverse the direction of rotation of said motor whereby said planetary gearing will op erate said first actuator means to close said doors;

- said device/ when the doors are again fully closed, 7. operating said switch means to deenergize said a motor; manually operable means operatively associated with said device and effective, when operated, to uncouple said motor from said planetary gearing and to release said brake means to provide for movement of the landing gear and and a centrifugal governor coupled between said motor and said planetary gearing and effective to limit the rate of operation of the landing gear and doors.

19. An aircraft landing gear and landing gearbay door operating mechanism comprising,- in combination, an electric motor; first actuator means operable to move the doors between open and, closed positions; second actuator means operable to move the landing gear between extended and retracted positions; planetary gearing including a driving element coupled to said motor,

a first driven element coupled to said first actuator means and a second driven element coupled to said second actuator means; brake means normally locking said second driven ele torque responsive device coupled between said motor and said driven element; switch means selectively operable by said device, when the torque thereon exceeds a predetermined value, to

' deenergize or reverse the direction of rotation of said motor; said torque responsive device, when such landing gear is fully retracted, operating said switch means to reverse said motor whereby said driving element, through said first driven element, will operate said first actuator means to close such doors; said device, when the doors are,

fully closed, operating said switch means to deenergize said motor; said torque responsive device, when said motor is energized with the landing gear in the retracted position and th doors have iully opened, operating said switch means to reverse the direction of rotation of said motor whereby said driving element, through said second driven element, will operate said second actuator means to extend the landing gear and, said device, when the landing gear is fully extended, operating said switch means to again reverse the direction of rotation of said motor whereby said planetary gearing will operate said 7 first actuator means to close said doors; said device, when the doors are again fully closed, op-

erating said switch means to deenergize said crated,

sociated with said device and effective, when opto uncouple said motor from said planetary gearing and to release -said brake 1 'means to provide for movement the landing gear and doors under the influence of gravity; a centrifugal governor coupled between said motor 1 and said planetary gearing and eflective to limit the rate of operation of the landing gear and doors; and a control circuit for said motor ineluding said switch means and conditioned, upon deenergization of said motor, to effect dynamic braking thereof. l v 1 20. n torque limiting mechanism for a motor drive system comprising, in combination, a'gear unit including a driving element adapted to be coupled to the motor, a driven element, and a normally stationary movable element effective to transmit torque from said driving element to said driven element; a sleeve pivotally mounted in said unit; motor controlling switch means operabiy by pivotal movement of said sleeve; ad- Justabie means restraining pivotal movement of said sleeve; a plunger slidably mounted in said sleeve; means normally urging said plunger to engage said movable element to prevent oscillation thereof; said movable element, when the torque on said mechanism exceeds a predetermined amount, oscillating totvpivot said sleeve and operate said switch means to alter the energization of said motor; and manually operable means selectively operable to disengage said plunger from 'said movable element to operatively un-' couple the motor from said driven element.

VICTOR J. PLOTKIN. 

